Ofcom today fined the BBC £150,000 over the "Sachsgate" row, describing the Radio 2 broadcast of messages left by Jonathan Ross and Russell Brand on actor Andrew Sachs's voicemail as "gratuitously offensive, humiliating and demeaning".

The watchdog said the scale of the fine reflected the "extraordinary nature and seriousness" of the BBC's failures and the resulting breaches of the broadcasting code.

Ofcom said the corporation had broadcast "explicit, intimate and confidential information" about Sachs's granddaughter, Georgina Baillie, without her consent in Brand's Radio 2 programmes that aired on 18 October and 25 October last year.

"This not only unwarrantably and seriously infringed their privacy but was also gratuitously offensive, humiliating and demeaning," Ofcom said.

The media regulator said it had imposed a fine of £70,000 for breaches of the broadcasting code on standards and over the Radio 2 broadcast of offensive material, and a further £80,000 for the unwarranted infringement of Sachs's and Baillie's privacy.

Ofcom said that despite the BBC considering Brand's show to be "high risk", it had ceded responsibility for some of management of the programme to people working for the comedian. "The presenter's interests had been given greater priority than the BBC's responsibility to avoid unwarranted infringements of privacy and minimise the risk of harm and offence and to maintain generally accepted standards," today's Ofcom report said.

Ofcom identified six "underlying flaws" in the BBC's compliance systems, including a "lack of clarity" about the role of the show's executive producer, a senior figure at the management agency that represented Brand; the failure of the executive producer to attend a BBC Safeguarding Trust compliance course, despite it being a condition of the production contract; the failure of the executive producer to sign off compliance forms; no proactive testing and "insufficient monitoring" of the compliance systems in the BBC audio and music department in general; an "unacceptable conflict of interest" for the line producer seconded from the BBC to Brand's production company; and a "lack of clarity" about who at the BBC had editorial oversight of the show.

Ofcom said these "overall weaknesses" set the scene for the "very serious failures of the BBC's compliance systems that resulted in the repeated broadcast of exceptionally offensive, humiliating and demeaning material".

The regulator said failures included no senior manager at Radio 2 listening to the 18 October pre-recorded programme; a failure to obtain the consent of Sachs to broadcast the voicemail messages; no attempt to obtain consent from Baillie; and the failure to complete and submit compliance forms before the broadcast.

Ofcom said it welcomed the BBC's assurances about improving compliance but said it was "concerned" that it had received similar assurances as recently as summer last year following the string of deception scandals.

In its response to Ofcom, the BBC said that the two broadcasts in Brand's Radio 2 show should "never have happened" and that they were "unacceptable and demonstrably failed to meet the BBC's editorial standards".

However, the BBC added that as neither Sachs nor Baillie had complained to Ofcom about the broadcasts infringing their privacy, it was unprecedented for the regulator to investigate the incident. However, Ofcom said it had received a copy of the original complaint to the BBC from Sachs' agent, in which it stated he had been "upset" by his treatment.

This is only the second time Ofcom has imposed a fine on a broadcaster over privacy, following a £75,000 penalty for London radio station Kiss FM in June 2006.

In a statement, the BBC Trust said it regretted that the "serious breaches" had led to a financial penalty and the "loss of licence fee payers' money as a result".

"The Trust's priority remains ensuring that the highest editorial standards are maintained to safeguard licence fee payers from offence and ensuring that individuals' privacy is not breached," the BBC Trust added.

A spokesman for BBC management said: "The BBC has since taken comprehensive action to deal with what were unacceptable failures in editorial judgement and compliance which led to the broadcast."

The row was sparked after the lewd comments were broadcast in a pre-recorded segment on Brand's Saturday night Radio 2 show on 18 October last year. The following week, Brand's apology song, in which he repeated allegations about Baillie, was again broadcast.

There were only two complaints in the week after the show was broadcast, but after the Mail on Sunday splashed on the story the following weekend and media coverage exploded, this number rocketed to a total of 44,790.

Brand subsequently resigned, along with Radio 2 controller Lesley Douglas and head of compliance Dave Barber. Ross was suspended without pay for three months, although he has now returned to presenting his BBC TV and radio shows.

Ofcom's highest fine imposed on the BBC was £400,000 in July last year for unfair conduct in viewer and listener competitions across eight TV and radio shows, including Children in Need and Comic Relief, although that was for deception, rather than causing offence.

The previous biggest scandal concerning taste and decency to hit the BBC was over Jerry Springer: the Opera, which sparked 64,000 complaints after it was broadcast in January 2005. However, Ofcom later concluded that the show was an "important work" that had not breached its codes on broadcasting.

ITV's £5.7m fine in May 2008 is the biggest financial penalty imposed on a UK broadcaster, over the "abuse" of premium-rate phone lines in a host of hit shows including Ant and Dec's Saturday Night Takeaway, Ant and Dec's Gameshow Marathon and Soapstar Superstar.

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